Emma Raducanu's former coach has revealed he split with the teen prodigy because there were numerous 'red flags' during their short stint together.
Raducanu sent shockwaves through the tennis community after the then 18-year-old became the first qualifier to ever win the US Open.
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However, since winning her maiden slam she has dropped down the world rankings and struggled with consistency on the WTA Tour.
Most recently, Raducanu pulled out of the Transylvania Open with a wrist injury having lost in the first round of both the Ostrava Open and the US open.
And during her difficult adjustment period on the WTA Tour, Raducanu has seen a number of coaches join and leave her team.
Tursunov was with British star for two months - during her US Open campaign - before he opted to leave at the end of the regular season to join World No.13 Belinda Bencic.
It leaves former US Open champion Raducanu searching for a fifth coach in just 16 months.
And in a candid interview with Tennis Majors, Tursunov claimed there were a number of 'red flags' during his time with the 18-year-old star that meant he couldn't continue.
"We didn't agree on the terms and there were some red flags that just couldn't be ignored,” Tursunov told the publication.
“Our trial period was over at the US Open but I stuck around, trying to see if there was going to be a way to impress the team. I really wanted to make it work.”
Tursunov admitted that he was walking away from Raducanu regardless of whether he had another job lined-up, but afterwards found work with Bencic.
Despite departing Raducanu's team, Tursunov was complimentary of her skills.
Tursunov said that despite some criticism since her US Open win, Raducanu was down to earth and workd hard during training.
“First of all, she’s absolutely great, she’s a hard worker and she doesn’t think or act like she’s a superstar," he said.
Emma Raducanu prepares for Billie Jean King Cup
Raducanu hasn't played since withdrawing from the Transylvania Open, which many thought would signal the end to her season.
However, the 18-year-old was named in the Billie Jean King Cup team.
And since Tursunov's departure, Raducanu has been working with Andy Murray’s former fitness coach Jez Green as she targets a return to the finals in Glasgow in December.
While there is hope Raducanu can take part for Great Britain, doubt still remains over her participation after it appeared she wouldn't take part in anymore individual events this year.
Team captain Anne Keothavong was hopeful Raducanu could play after pointing out she still has a few weeks of rest before the tournament in November.
"This is a strong squad for the Billie Jean King Cup Finals, and we're keen to finish the year on a high in front of the passionate crowds in Glasgow," she said of the announcement.
"All four players have experience in the competition and great memories of playing for GB."
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